Extracellular dopamine in the rat prefrontal cortex during reward-, punishment- and novelty-associated behaviour. Effects of diazepam

Extracellular dopamine in the rat prefrontal cortex during reward-, punishment- and... Variations of extracellular dopamine (DA ext ) levels in prefrontal cortex were assessed by in vivo microdialysis. In rats trained in an operant fixed interval (FI 30s ) schedule of food delivery, acute exposure to contingent foot shocks resulted in a suppression of responding that was reversed by diazepam (4 mg/kg, ip). No changes in cortical DA ext levels occurred during this period in both control and treated rats. By contrast, in control rats, cortical DA ext levels increased (+25–40%) during the nonpunished component of the operant session, and during noncontingent food delivery (+25%). Control rats placed into an unfamiliar brightly lit openfield exhibited a marked increase in cortical DA ext levels (+100%). This effect occurred neither in rats given diazepam at a dose (2 mg/kg) which stimulated motor activity, nor during a second exposure to the openfield. In conclusion, a benzodiazepine-sensitive activation of mesoprefrontal DA neurones is induced by exposure to novel stressful surroundings and by food availability and consumption. The fact that cortical DA ext levels remained unchanged in rats that exerted complete control upon negative stimuli indicates that an activation of the mesoprefrontal DA system is not required for punishment-induced behavioural blockade. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Pharmacology Biochemistry and Behavior Elsevier

Extracellular dopamine in the rat prefrontal cortex during reward-, punishment- and novelty-associated behaviour. Effects of diazepam

Loading next page...
 
/lp/elsevier/extracellular-dopamine-in-the-rat-prefrontal-cortex-during-reward-YfWjiH3g9u
Publisher
Elsevier
Copyright
Copyright © 2001 Elsevier Science Inc.
ISSN
0091-3057
eISSN
1873-5177
DOI
10.1016/S0091-3057(01)00492-0
Publisher site
See Article on Publisher Site

Abstract

Variations of extracellular dopamine (DA ext ) levels in prefrontal cortex were assessed by in vivo microdialysis. In rats trained in an operant fixed interval (FI 30s ) schedule of food delivery, acute exposure to contingent foot shocks resulted in a suppression of responding that was reversed by diazepam (4 mg/kg, ip). No changes in cortical DA ext levels occurred during this period in both control and treated rats. By contrast, in control rats, cortical DA ext levels increased (+25–40%) during the nonpunished component of the operant session, and during noncontingent food delivery (+25%). Control rats placed into an unfamiliar brightly lit openfield exhibited a marked increase in cortical DA ext levels (+100%). This effect occurred neither in rats given diazepam at a dose (2 mg/kg) which stimulated motor activity, nor during a second exposure to the openfield. In conclusion, a benzodiazepine-sensitive activation of mesoprefrontal DA neurones is induced by exposure to novel stressful surroundings and by food availability and consumption. The fact that cortical DA ext levels remained unchanged in rats that exerted complete control upon negative stimuli indicates that an activation of the mesoprefrontal DA system is not required for punishment-induced behavioural blockade.

Journal

Pharmacology Biochemistry and BehaviorElsevier

Published: May 1, 2001

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create folders to
organize your research

Export folders, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off